1. Field of the Invention
The present invention relates to liquid activation and electrolytic apparatuses and liquid activation and electrolytic methods and, more particularly, to novel and innovative liquid activation and electrolytic apparatus and liquid activation and electrolytic method that can efficiently generate hydrogen gas or the like by starting electrolysis at a direct-current low voltage by facilitating the ionization of a liquid portion of an electrolytic solution by activating the liquid portion.
2. Description of the Related Art
In general, an electrode in an electrolytic cell in which the electrolysis of a liquid is performed is a starting point which performs the electrolysis of a liquid such as seawater by causing a chemical reaction by consuming electricity.
As such an electrode, there are a positive pole and a negative pole; at the positive pole, an oxidation reaction by which electrons are released occurs and, at the negative pole, a reduction reaction by which the electrons are accepted occurs.
Moreover, the electrodes are classified into soluble electrodes and insoluble electrodes. Examples of the soluble electrodes include a carbon electrode, an aluminum electrode, a Cu electrode, an Sn electrode, and a Pb electrode.
Examples of the insoluble electrodes include a Pt/Ti electrode which is a metal-plating electrode and an IrO2/Ti electrode which is a metal-sintering electrode.
Of these electrodes, the Pt/Ti electrode which is a metal-plating electrode that is often used in the electrolysis of water is formed by placing an electrocatalyst on a valve metal and using a functional material, such as titanium (a Ti material), which is not eluted even when the material is subjected to polarization in such a way that the material becomes positive. Thus, the following matters are important for the electrode.
(a) Having an electrocatalytic function which differs depending on an electrocatalytic metal.
(b) Having electrical bonding power between a base material (such as a Ti material) and a plating metal (a catalyst).
(c) Not suffering from deterioration such as separation and wear because of the physical strength of the plating metal (the catalyst).
(d) Having a long life as the electrode because of the chemical durability of an electrocatalyst.
(e) Reducing electrode production costs (which requires the technology to make a film as thin as possible).
An electrolysis voltage is a value given by the following expression, and the amount of energy required for an electrolytic operation is determined depending on whether this value is large or small.
Electrolysis voltage (Volt)=theoretical electrolysis voltage+overvoltage+solution resistance
At low current density, the Pt/metal electrode is suitable and, in that case, catalytic performance is important.
On the other hand, at high-density currents, an ft-Pt oxide electrode is suitable and oxygen-resistance performance is important.
An electrocatalytic surface has projections and depressions, and these projections and depressions cause a difference in the value of a flowing current in an electrolytic operation in which the distance between the positive and negative poles is small, which makes the value of effective current density larger than the value of apparent current density and exerts a great influence on the electrode life.
In an electrolytic reaction, there is a strong correlation between the ease of adsorption and diffusion of a substance which is subjected to oxidation-reduction to the electrocatalytic surface and the reaction efficiency, and therefore the selection of an electrode which maximizes desired chemical reaction efficiency and the accuracy of making the electrode surface are important matters.
Examples of a combination of a positive pole and a negative pole depending on the type of an electrolytic solution are listed in Table 1 below.
TABLE 1Combination of electrodesPositiveNegativeelectrodeElectrolytic solutionelectrode1platinumsodium chloride aqueous solutionplatinum2carbon rodcopper sulfate (I) aqueous solutioncopper3platinumsodium hydroxide aqueous solutionplatinum4copperhydrochloric acidcopper5carbon rodpotassium iodide aqueous solutioncopper
In Japanese Unexamined Patent Application Publication No. 2013-99735, a hydrogen water generation device including an electrolysis treatment tank that is configured to be capable of containing treated water, electrodes that are configured to perform the electrolysis of the treated water contained in the electrolysis treatment tank, and a current control device that passes a current for performing the electrolysis through the electrodes and controls the current density of the current to be 0.75 A/dm2 or less is proposed.
However, under present circumstances, as with the hydrogen water generation device proposed in Japanese Unexamined Patent Application Publication No. 2013-99735, no electrolysis apparatus can efficiently generate hydrogen gas or the like by starting electrolysis at a direct-current low voltage.